The elephant of global warming

By Hsu Huang-hsiung 許晃雄

The upcoming arrival of former US vice president Al Gore is certain to set off a new wave of discussion about global warming in Taiwan. The topic is like an elephant with a fever being cared for by a group of blind people.

Some say the elephant doesn't have a fever and that only the room temperature has increased, while some touch the elephant's tusks and say the temperature hasn't risen at all. Global warming is a multi-faceted issue. Each person has his own observations and attitude, and sometimes it's like the famous Indian legend of the the blind men and the elephant -- each man touches the elephant and all three come to different conclusions as to what it is.

Some people passionately call for humans to protect the earth. Some have a more conservative attitude, saying that the sun is getting stronger and that global warming isn't necessarily related to what humans do. They believe that global warming will actually make the earth's climate milder.

Then there are some people who quote biased reports to refute global warming theories. Some people question why weather bureau data differs from that in media reports. I am a climatology researcher who has also come to feel the elephant and report my observations.

Over the past 100 years, temperatures in Taiwan have risen twice as fast as the global average. Taiwan, northeast Asia, Siberia and the northern Asian and European continents are all experiencing this kind of phenomenon. Other areas in the 20th century experienced a decline in temperature, making temperature increases over the last 100 years less significant. This climatic diversity is clearly influenced by different factors.

Over the last 30 years, the rate of global temperature increase has suddenly escalated to about three times its pace over the last 100 years, or about two degrees per 100 years. Temperatures in Taiwan have increased at about the same rate, with winter temperatures rising more than summer temperatures.

The documented changes over the past three decades reflect global warming in its most obvious form, with almost all regions of the globe becoming hotter.

Climatic diversity seems to be gradually disappearing. Biological diversity is beneficial to ecological and environmental sustainability, while climatic diversity helps to maintain a stable climate.

More importantly, over the past 30 years land temperatures have clearly increased faster than ocean air temperatures -- whereas during the previous 100 years, they warmed at about the same rate. Climatic modeling for future global warming shows a similar trend. By the end of the 1980s, climatologists had predicted that greenhouse gas emissions couldn't be checked and global temperatures would continue to rise.

Greenhouse gas emissions have steadily risen over the last 30 years, while the global warming trend has become more evident. These phenomenons have deeply worried many climatologists.

The UN's Intergovernmental Panel on Climate Change (IPCC) recently issued its fourth report, stating that it's very possible that the global warming experienced over the past 50 years could have been influenced by humans.

It said that the average global temperature will rise by 1.1oC to 6.4oC by the end of the 21st century, possibly intensifying storms and droughts in some areas.

Some people doubt the reliability of these results because climate modeling has many flaws and climate predictions tend to be inaccurate. These skeptics believe there is much uncertainty about global warming. There is some basis for all of these theories, but modern science doesn't provide firmer predictions, instead emphasizing probabilities and possibilities.